A lithium-ion secondary battery comprises a positive electrode, a negative electrode, and an electrolyte present between these two electrodes; and charging and discharging are mediated by lithium ions in the electrolyte moving back and forth between the two electrodes. As the active material for reversely storing and releasing lithium ions at the negative electrode, various carbonaceous materials have been used primarily. Recently, materials have been investigated to replace carbonaceous materials. Technical literatures relating to negative electrode materials other than carbonaceous ones include Patent Document 1.